Wafer polishing system and wafer transport method

Abstract

The present invention discloses a wafer polishing system, which includes a polishing unit having a wafer transport channel with at least two working positions, and a polishing module including a polishing table and a polishing arm that can move a wafer relative to the driving of the polishing table, and the wafer loading / unloading table can be moved between the working positions, and a transmission structure is provided between adjacent polishing units to transport the wafer between the two working positions along a first track on the wafer transport channel, and / or the wafer loading / unloading table can be moved between adjacent polishing units, and / or a transport structure is provided between the polishing unit and an external turntable to transport the wafer between the two working positions along a second track on the wafer transport channel. The present invention further discloses a wafer transport method. The tracks of the present invention are all on the wafer transport channel, do not occupy additional space, are rational in layout, are flexible in process, have high processing efficiency, and have high transport stability.

Description

[Technical Field]

[0001] The present invention belongs to the technical field of semiconductor integrated circuit chip manufacturing, and more particularly to a wafer polishing system and a wafer transport method. [Background technology]

[0002] A chemical mechanical polishing and planarization apparatus typically includes a semiconductor front-end module (EFEM), a cleaning unit, a polishing unit, and a transfer module. The EFEM primarily includes a wafer storage cassette, a wafer transfer robot arm, and an air purification system. The cleaning unit primarily includes a variable number of megasonic cleaning components, roller brush cleaning components, a drying component, and a device for transporting wafers between components. The polishing unit primarily includes a polishing table, a polishing head, a polishing liquid supply system, and a polishing pad dressing system. The transfer module includes a series of robot arms and moving tables that transport wafers waiting to be polished from the EFEM to the polishing unit and polished wafers from the polishing unit to the cleaning unit. In addition to factors such as the number, relative placement, and processes of the polishing and cleaning units affecting the overall operating efficiency of the machine, the transport method and transport path of the transport system also play an important role in determining the overall operating efficiency of the machine.

[0003] In the currently disclosed chemical mechanical planarization apparatus, the polishing module includes two rows of polishing unit arrays, each row of polishing units includes multiple sets of polishing units, the loading and unloading tables corresponding to the two rows of polishing unit arrays are arranged vertically in the row direction of the polishing unit arrays, and the working section of the top transport device is arranged vertically above the loading and unloading tables to complete the transport of wafers between other loading and unloading areas and the loading and unloading tables. If necessary, the top transport devices of each set can form a cascade to complete the transport of wafers between each loading and unloading table, thereby realizing the flow of wafers throughout the polishing unit arrays.

[0004] However, the top transport device has a relatively large transport load. Furthermore, due to the special structure of the polishing module, it is not possible to add another transport device. Therefore, wafers are transported from the polishing unit solely by the top transport device, resulting in a lack of process flexibility. Furthermore, because the working section of the top transport device is located vertically above the loading / unloading table, it must descend to the loading / unloading table when loading or unloading wafers. This process takes a significant amount of time. Especially when alternating between double-disk and triple-disk processes, the top transport device is responsible for the wafer loading and unloading tasks when transporting wafers between different rows of polishing units, significantly reducing the wafer transport efficiency during the process. Furthermore, relying solely on the top transport device for wafer loading and unloading and transport increases the equipment's transport time and simultaneously increases the risk of impurities during the wear process. This transport method places high demands on the wafer transport capacity and stability of the top transport device. If the top transport unit fails, wafers will not be transported from the polishing area in a timely manner, resulting in product defects. Summary of the Invention

[0005] SUMMARY OF THE INVENTION To solve the problems of the prior art, the present invention provides a wafer polishing system that does not occupy extra space and one or more methods for transporting the wafer polishing system.

[0006] The technical solution that the present invention uses to solve the technical problem is a wafer polishing system that includes a polishing unit.

[0007] The polishing unit includes a wafer transfer channel and a polishing module.

[0008] The polishing module includes a polishing table and a polishing arm that can be driven to move the wafer relative to the polishing table to accomplish the polishing process.

[0009] The wafer transport channel has at least two working positions, and the wafer loading / unloading table is movable between the working positions.

[0010] A transfer structure is provided between adjacent polishing units for transferring wafers between the working positions along a first track on the wafer transfer channel.

[0011] And / or, the wafer loading / unloading table can move between adjacent polishing units.

[0012] And / or, a transport structure is provided between the polishing unit and the external turntable for transporting wafers between the working positions of the polishing unit and the external turntable along a second track on the wafer transport channel.

[0013] The system further includes a top transport mechanism for transporting wafers between all of the polishing units along a third track on the wafer transport channel.

[0014] Alternatively, the top transport mechanism transports wafers between any polishing unit and the external turntable along a fourth track above the wafer transport channel.

[0015] Furthermore, the top transport mechanism is located above the transfer structure and / or the transport structure.

[0016] Furthermore, the transfer structure includes a clamping unit for clamping the wafer, and a flipping unit used to flip the clamping unit and the wafer forward or backward in the wafer transport channel.

[0017] Furthermore, the transfer structure includes a clamp unit for clamping the wafer, a translation unit used to translate the clamp unit and the wafer within the wafer transport channel, and a lifting unit used to raise or lower the entire transfer structure so that it is positioned below or above the polishing table.

[0018] The transfer structure further includes a base and a telescopic arm connected thereto and extending downward from an upper region of the polishing table or extending upward from a lower region of the polishing table.

[0019] Furthermore, the transfer structure includes an auxiliary work position located between adjacent polishing units and an auxiliary transfer unit located above or below the auxiliary work position, and the wafer loading / unloading tables of the adjacent polishing units can both be moved to the auxiliary work position, and the auxiliary transfer unit is used to adsorb wafers on the auxiliary work position or to place wafers on the wafer loading / unloading tables on the auxiliary work position, and the auxiliary transfer unit is located below or above the polishing tables.

[0020] Furthermore, at least a portion of the movement path of the wafer loading / unloading table that can move between adjacent polishing units overlaps, and the overlapping path includes at least one working position.

[0021] Furthermore, there is a gap between adjacent polishing units.

[0022] Furthermore, a transmission structure is provided between adjacent working positions of the same polishing unit.

[0023] Furthermore, the transmission structure is the same as the transport structure.

[0024] The present invention further discloses a wafer transport method for a wafer polishing system, wherein the wafer polishing system includes a polishing unit having a wafer transport channel with at least two working positions, and the wafer loading / unloading table can move between the working positions, and the wafer transport method includes the following steps:

[0025] The transfer structure transports the wafer from the working position of one polishing unit to the working position of another adjacent polishing unit along a first track on the wafer transport channel.

[0026] Furthermore, the transport structure transports wafers from the working position of the polishing unit to the external turntable or from the external turntable to the working position of the polishing unit along a second track on the wafer transport channel.

[0027] It further includes the following steps:

[0028] Using a transmission structure and a wafer loading / unloading table, the wafer is transported between working positions of the polishing unit along a first track until it enters a target working position, and the polishing arm picks up the wafer on the working position and moves it to the polishing table to perform the polishing process.

[0029] Alternatively, the top transport mechanism is used to transport the wafer between the working positions of the polishing unit along the third track, and directly enter the target working position, and the polishing arm picks up the wafer on the working position and moves it to the polishing table to perform the polishing process.

[0030] Alternatively, the transfer structure, the wafer loading / unloading table and the top transport mechanism are used to transport the wafer between the working positions of the polishing unit along the first and third tracks until it enters the target working position, and the polishing arm picks up the wafer on the working position and moves it to the polishing table to perform the polishing process.

[0031] The first and third tracks are both located on the wafer transport channel.

[0032] It further includes the following steps:

[0033] A transfer structure is used to transfer the wafer along the second track from the external turntable to a working position in the polishing unit.

[0034] Alternatively, a top transport mechanism is used to transport the workpiece from the external turntable to the working position of the polishing unit along the third track.

[0035] The second and third tracks are located on the wafer transport channel.

[0036] Furthermore, the number of the polishing units is plural, the polishing process is divided into plural stages, and the polishing units located in the downstream stages are installed close to the center of the wafer transport channel.

[0037] The beneficial effects of the present invention are: 1) the first, second, and third tracks are all located on the wafer transport channel, so they do not occupy additional space and are arranged rationally; 2) the transport structure, transmission structure, and top transport mechanism can be combined, providing high process flexibility and no interference; the installation of the transport structure and transmission structure does not adversely affect the top transport mechanism, allowing the top transport mechanism to always pass through the polishing unit without interference; using this arrangement contributes to reducing the transport stroke and significantly improving the processing efficiency of the chemical mechanical planarization apparatus; 3) the risk of wear impurities during the transport process is not increased; 4) the transport stability is high; when one transport device breaks down, the other transport device will enter operation, ensuring that the wafer is sent out of the polishing area in a timely manner and ensuring the quality of the wafer product; and 5) an independent wafer transport channel is built between adjacent wafer receiving tables, which can be used alone or in combination with the top transport mechanism, increasing the flexibility of wafer transport in the polishing area, reducing the wafer transport pressure of the top transport device on the wafer placement table, and improving the transport efficiency of the entire machine. [Brief explanation of the drawings]

[0038] [Figure 1-1] 1 is a schematic diagram of a wafer polishing system according to a first embodiment of the present invention, in this case including two polishing units. [Figure 1-2] 1 is a schematic diagram of a wafer polishing system according to a first embodiment of the present invention, in this case having a gap between two polishing units. [Figure 1-3] FIG. 2 is a schematic diagram showing a single polishing unit according to the first embodiment of the present invention, which has only one working position. [Figure 1-4] 2A and 2B are schematic diagrams of a polishing unit including two polishing modules and a polishing unit including one polishing module according to the first embodiment of the present invention. [Figure 1-5] FIG. 1 is a schematic diagram showing polishing units according to a first embodiment of the present invention, each of which includes a single polishing module. [Figure 2]1 is a schematic diagram of a wafer polishing system according to a first embodiment of the present invention, in which the transmission structure includes a clamping unit, a translation unit, and a lifting unit. [Figure 3] 1 is a schematic diagram of a wafer polishing system according to a first embodiment of the present invention, in which the transfer structure includes a base and an extendable arm. [Figure 4] 1 is a schematic diagram of a wafer polishing system according to a first embodiment of the present invention, in which the transfer structure includes an auxiliary working position and an auxiliary transition unit. [Figure 5] 1 is a schematic diagram 1 of a wafer polishing system according to a second embodiment of the present invention. [Figure 6] 2 is a schematic diagram 2 of a wafer polishing system according to a second embodiment of the present invention. [Figure 7] FIG. 10 is a schematic diagram of a top transport mechanism according to a third embodiment of the present invention. [Figure 8] FIG. 11 is a structural top view of a combination of a top transport mechanism and a polishing unit according to a third embodiment of the present invention. [Figure 9] FIG. 11 is a side view of a structure in which a top transport mechanism and a polishing unit are combined in accordance with a third embodiment of the present invention. [Figure 10] FIG. 10 is a schematic diagram of a wafer polishing system according to a fourth embodiment of the present invention. [Figure 11] 1 is a schematic diagram 1 of a wafer polishing system according to a fifth embodiment of the present invention. [Figure 12] 10 is a schematic diagram 2 of a wafer polishing system according to a fifth embodiment of the present invention. [Figure 13] 3 is a schematic diagram 3 of a wafer polishing system according to a fifth embodiment of the present invention. [Figure 14] 4 is a schematic diagram 4 of a wafer polishing system according to a fifth embodiment of the present invention. [Figure 15] FIG. 10 is a schematic diagram showing the positional arrangement of a wafer polishing system according to a sixth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0039] In order to help those skilled in the art to better understand the method of the present invention, the following clearly and completely describes the technical solutions in the embodiments of the invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without any creative efforts should fall within the scope of the claims of the present invention.

[0040] Embodiment 1 The wafer polishing system includes a polishing unit 1.

[0041] The polishing unit 1 includes a wafer transfer channel 2 and polishing modules 11 located on both sides of the wafer transfer channel 2, and the number of the polishing modules 11 is at least two.

[0042] The polishing module 11 includes a polishing table 111 and a polishing arm 112 that can move the wafer 3 relative to the polishing table 111 to perform a polishing process on the wafer 3 .

[0043] There are at least two work positions 21 on the wafer transport channel 2, and the wafer loading / unloading table 4 can move between the work positions 21.

[0044] Between adjacent polishing units 1, a transfer structure 5 is provided for transferring wafers 3 between working positions 21 of the two polishing units 1 along a first track on the wafer transfer channel 2.

[0045] The wafer transfer channel 2 does not necessarily have to be a definite area; any spatial area that the transfer structure 5 can reach can be defined as the wafer transfer channel 2 .

[0046] As shown in Fig. 1-1, there is no gap between two adjacent polishing units 1, and they are closely adjacent to each other. As shown in Fig. 1-2, a gap 9 may be provided between two adjacent polishing units 1 to function as a channel for transporting or receiving wafers in other directions.

[0047] As shown in Figure 2, the transmission structure 5 includes a clamp unit for clamping the wafer 3, a translation unit for translating the clamp unit and the wafer within the wafer transport channel 2, and a lifting unit for raising or lowering the clamp unit and the entire wafer so that the transmission structure 5 is positioned below or above the polishing table 111.

[0048] Of course, as shown in Figure 3, the transfer structure 5 may be another structure, for example, including a base 51 located within the wafer transport channel 2 and an extendable arm 52 connected to the base 51 and extending downward from the upper region of the polishing table 111 or extending upward from the lower region of the polishing table 111, the end of which may clamp the wafer 3.

[0049] The telescopic arm 52 may include a two-stage arm body or a three-stage arm body, and the grip at the end of the telescopic arm 52 may be a one-grip structure or a two-grip structure, and is not specifically limited.

[0050] The transfer mechanism 5 may be installed between two working positions of the same polishing unit 1, and the two working positions are respectively equipped with wafer loading / unloading tables that are fixed relative to each other.

[0051] Of course, one polishing unit 1 does not necessarily have two working positions, but may have only one working position. In this case, as shown in Figures 1-3, the transmission structure 5 is located between the two working positions of two adjacent polishing units.

[0052] The polishing unit 1 typically includes, but is not limited to, at least two polishing modules 11. One polishing unit 1 may include one polishing module 11. As shown in FIG. 1-4, in this case, the upper polishing unit 1 includes two polishing modules 11 located on both sides of the wafer transport channel 2, and the lower polishing unit 1 includes one polishing module 11. As shown in FIG. 1-5, in this case, the upper polishing unit 1 includes one polishing module 11, and the lower polishing unit 1 also includes one polishing module 11.

[0053] The transfer structure 5 may further include an auxiliary work position 53 located between adjacent polishing units 1 and an auxiliary transfer unit 54 located above or below the auxiliary work position 53. The wafer loading / unloading tables 4 of adjacent polishing units 1 can both move to the auxiliary work position 53, and the auxiliary transfer unit 54 is used to suck a wafer on the auxiliary work position 53 and then maintain the sucked state of the wafer until another wafer loading / unloading table 4 moves to the auxiliary work position 53, or to place a wafer on the wafer loading / unloading table 4 on the auxiliary work position 53. That is, when another wafer loading / unloading table 4 moves to the auxiliary work position 53, the auxiliary transfer unit 54 places the wafer on that wafer loading / unloading table 4.

[0054] 4, an auxiliary work position W5 is newly added between work positions W2 and W3 of adjacent polishing units 1, and both wafer loading / unloading tables 4 can move to the auxiliary work position W5. That is, the movement range of the wafer loading / unloading table 4 includes work positions W1, W2, and W5, as well as work positions W5, W3, and W4. An auxiliary transfer unit 54 is located above work position W5 and can load and unload wafers at work position W5, thereby indirectly transporting wafers between work positions W2 and W3.

[0055] The different structures of the transfer structure 5 can exist simultaneously, that is, transfer structures 5 of different structures can be used in combination in the same wafer transfer method.

[0056] After the polishing process of the wafer in the polishing module 2A is completed, the polishing arm H2 transfers the wafer to the working position W2, and then step 1 or step 2 is performed.

[0057] Step 1: Next, the wafer is transported to the working position W5, the auxiliary transfer unit 54 removes the wafer from the working position W5, the movable wafer loading / unloading table 4 at the working position W3 moves to the working position W5, the auxiliary transfer unit 54 places the wafer at the working position W5, and then transports it to the working position W3. The polishing arm H3 transports the wafer into the polishing module 1B for the polishing process.

[0058] Step 2: Next, the wafer is transported to working position W5, the auxiliary transfer unit 54 removes the wafer from working position W5, the movable wafer loading / unloading table 4 at working position W3 moves to working position W5, the auxiliary transfer unit 54 places the wafer at working position W5, and then transports it to working position W3. The movable wafer loading / unloading table 4 transports the wafer from working position W3 to working position W4, and the polishing arm H4 transports the wafer into polishing module 2B for the polishing process.

[0059] Of course, the auxiliary transfer unit 54 may be located below or above the polishing table 111 , in which case the transport track of the wafer 3 is still located on the wafer transport channel 2 .

[0060] Embodiment 2 Between the polishing unit 1 and the external turntable 6 , a transport structure 7 is provided for transporting the wafer 3 between the polishing unit 1 and the external turntable 6 along a second track on the wafer transport channel 2 .

[0061] The transport structure 7 includes a clamp unit 71 for clamping the wafer 3, and an inversion unit 72 for driving the clamp unit 71 and the wafer 3 so that they are inverted forward or backward within the wafer transport channel 2. Here, forward refers to the downward direction in FIG.

[0062] Specifically, as shown in FIG. 6, the wafer 3 can be transported to the working position W1 or W2 via the external turntable 6, and then moved from the working position W1 to the working position W2 or from the working position W2 to the working position W1 using the wafer loading / unloading table 4.

[0063] Naturally, the conveying structure 7 in this embodiment may have the same structure as the transmission structure 5 in the first embodiment, or may be used in combination with a different structure, and a detailed description thereof will be omitted.

[0064] Embodiment 3 The structures of the above-mentioned embodiments 1 and 2 may exist independently or simultaneously.Furthermore, one may exist simultaneously with the top transport mechanism 8 of this embodiment, and the three may be combined to transport wafers.

[0065] As shown in FIGS. 7 to 9, the top transport mechanism 8 transports the wafer 3 between all the polishing units 1 along a third track on the wafer transport channel 2.

[0066] Of course, the top transport mechanism 8 may also transport wafers between any of the polishing units 1 and the external turntable 6 along a fourth track located on the wafer transport channel 2 .

[0067] The top transport mechanism 8 is located above the transmission structure 5, or above the transport mechanism 7, or above both the transmission structure 5 and the transport mechanism 7.

[0068] Embodiment 4 Based on the above-described first to third embodiments, the wafer loading / unloading table 4 can be moved to the adjacent polishing unit 1.

[0069] 10, the movable wafer loading / unloading table 4 has a movement range including working positions W2, W3, and W4. After the polishing process of the wafer in the polishing module 2A is completed, the polishing arm H2 transports the wafer to working position W2. Then, step 1 or step 2 is performed.

[0070] Step 1: The movable wafer loading / unloading table 4 transports the wafer to the working position W3, and the polishing arm H3 carries the wafer into the polishing module 1B for the polishing process.

[0071] Step 2: The movable wafer loading / unloading table 4 transports the wafer to the working position W4, and the polishing arm H4 transfers the wafer into the polishing module 2B for the polishing process.

[0072] Embodiment 5 The wafer loading / unloading table 4 can be moved to the adjacent polishing unit 1, and only two wafer loading / unloading tables 4 are installed in two or more polishing units 1.

[0073] An example in which the number of polishing units 1 is two will be described.

[0074] As shown in FIG. 11, one of the wafer loading / unloading tables 4 is at a working position W1, and another wafer loading / unloading table 4 moves between working positions W2, W3 and W4.

[0075] Alternatively, as shown in FIG. 12, one of the wafer loading / unloading tables 4 moves between the working position W1 and the external turntable S1, and another of the wafer loading / unloading tables 4 moves between the working position W2, the working position W3 and the working position W4.

[0076] An example in which the number of polishing units 1 is three will be described.

[0077] As shown in FIG. 13, one of the wafer loading / unloading tables 4 moves between working position W1, working position W2 and working position W3, and another wafer loading / unloading table 4 moves between working position W4, working position W5 and working position W6.

[0078] At least some of the movement paths of the wafer loading / unloading tables 4 that can move between adjacent polishing units 1 overlap, and at least one work position 21 is included in the overlapping path. As shown in FIG. 14, one wafer loading / unloading table 4 may move between work position W1, work position W2, and work position W3, and may also move to work position W4, and another wafer loading / unloading table 4 may move between work position W4, work position W5, and work position W6, and may also move to work position W3. In this case, the area between work position W3 and work position W4 is the overlapping movement path of the two wafer loading / unloading tables 4. Work position W3 and work position W4 are included in the overlapping movement paths. Embodiment 6 A wafer transport method for a wafer polishing system including a polishing unit (1) having a wafer transport channel (2) with at least two work positions (21), and a wafer loading / unloading table (4) that can move between the work positions (21).

[0079] The first wafer transfer method includes the following steps.

[0080] Between adjacent polishing units 1 , the transfer structure 5 transfers the wafer 3 between the working positions 21 of the adjacent polishing units 1 along a first track on the wafer transport channel 2 .

[0081] The second wafer transfer method includes the following steps.

[0082] Between the polishing unit 1 and the external turntable 6, a transport structure 7 transports the wafer 3 between the polishing unit 1 and the working position of the external turntable 6 along a second track on the wafer transport channel 2.

[0083] The above two steps of the wafer transfer method may be performed independently or in combination.

[0084] The third wafer transfer method includes the following steps.

[0085] Using the transmission structure 5 and the wafer loading / unloading table 4, the wafer 3 is transported along the first track between the working positions 21 of the polishing unit 1 until it reaches the target working position, and the polishing arm 112 picks up the wafer 3 on the working position 21 and moves it to the polishing table 111 to perform the polishing process.

[0086] Alternatively, the top transport mechanism 8 is used to transport the wafer 3 along the third track between the working positions 21 of the polishing unit 1, and directly enter the target working position, and the polishing arm 112 picks up the wafer 3 on the working position 21 and moves it to the polishing table 111 to perform the polishing process.

[0087] Alternatively, the transmission structure 5, the wafer loading / unloading table 4 and the top transport mechanism 8 are used to transport the wafer 3 between the working positions 21 of the polishing unit 1 along the first and third tracks until it enters the target working position, and the polishing arm 112 picks up the wafer 3 on the working position 21 and moves it on the polishing table 111 to perform the polishing process.

[0088] Both the first and third tracks are located on the wafer transfer channel 2.

[0089] The fourth wafer transfer method includes the following steps.

[0090] Based on the third wafer transport method, the transport structure 5 is further used to transport the wafer 3 from the external turntable 6 to the working position 21 of the polishing unit 1 along the second track.

[0091] Alternatively, a top transport mechanism is used to transport the workpiece from the external turntable 6 to the working position 21 of the polishing unit 1 along the third track.

[0092] Both the second and third tracks are located on the wafer transport channel 2.

[0093] When using the fourth wafer transport method, if there are multiple polishing units 1 and the polishing process is divided into multiple stages, the polishing units 1 in the downstream stages are installed close to the center of the wafer transport channel 2.

[0094] In this wafer polishing system, the top transport mechanism, the transmission structure, and the transport structure may be used solely for loading or unloading wafers, or may be involved in loading and unloading according to a transport schedule.

[0095] (1) When the top transport mechanism and transmission structure, transport structure is applied only to the loading or unloading of wafers, it can be understood that one of the top transport mechanism and transmission structure, transport structure is responsible only for loading wafers, while the other is responsible only for unloading wafers.

[0096] (2) When the top transport mechanism and transmission structure, the transport structure, can be applied to wafer loading or unloading, these two transport devices can be involved in wafer loading or unloading according to different processes, which can be understood to realize flexible scheduling of wafer transport.

[0097] Generally, wafer polishing processes are divided into single-disk, double-disk, and triple-disk processes according to the number of polishing modules 11 used in combination.

[0098] As shown in Figure 14, the external turntable 6 is represented by S1, the working positions 21 are represented by W1, W2, W3, W4, W5, and W6, the polishing table 111 is represented by P1, P2, P3, P4, P5, and P6, and the polishing arm 112 is represented by H1, H2, H3, H4, H5, and H6.

[0099] A single disk process will be taken as an example.

[0100] (1) Remote table transport The single-disk process uses only one of the six (2, 3, 4, 5, and more) polishing modules 11 for the planarization process. After the wafer enters the external turntable S1 via the EFEM, it can be transported from the top transfer mechanism 8 on both sides to a remote table (away from the external turntable 6), such as working positions W5, W6 (and Wi, Wi+1 (i≥7) further away). Among them, the wafer located at the farthest working position W6 is directly loaded onto the polishing table P6 by the polishing arm H6, or the wafer on the working position W5 is loaded onto the polishing table P5 by the polishing arm H5.

[0101] (2) Remote table transfer The wafers on the proximity tables (proximity to the external turntable 6) polishing tables P1, P2 can be sequentially transported from the external turntable S1 by the transfer structure 5 or the transfer structure 7 of Embodiment 1 and Embodiment 2. After the wafer is transported to the working position W1, it is loaded onto the polishing table P1 by the polishing arm H1 and transferred, or after translating from the working position W1 to the working position W2, it is loaded onto the polishing table P2 by the polishing arm H2 and transferred.

[0102] (3) Central polishing unit transfer Two wafers, such as P3, P4 (Pn, n < i) of the central polishing unit, may be directly carried in by the top transfer mechanism 8, or may be transported by combining different transfer structures.

[0103] Among them, the wafer on the polishing table P3 is transported from the external turntable S1 to the working position W1 by the transfer structure 5 or the transfer structure 7 in Embodiment 1 and Embodiment 2, and after translating from the working position W1 to the working position W2, it is carried into the working position W3 by the transfer structure 5 in Embodiment 1.

[0104] Even when the transfer structure 5 or the transfer structure 7 is congested, a wafer positioned on the external turntable S1 can be transferred directly to the working position W2 by the top transfer mechanism 8, then further transferred to the working position W3 by the transfer structure 5, and finally loaded onto the polishing table P3 by the polishing arm H3. A wafer on the polishing table P4 can be transferred to the working position W4 by the top transfer mechanism 8, and then loaded onto the polishing table P4 by the polishing arm H4. Alternatively, the wafer on the polishing table P4 can be transferred to the aforementioned working position W3, then translated to the working position W4, and then loaded onto the polishing table P4 by the polishing arm H4.

[0105] Similarly, wafer removal is performed according to the principle that the remote section is given priority by the top transport mechanism 8, and wafers on remote tables, such as polishing tables P5 and P6 (and further away tables Pi and Pi+1 (i≧7)), are unloaded from polishing arms H5 and H6 (and Hi and Hi+1 (i≧7)) to working positions W5 and W6 (and further away tables Wi and Wi+1 (i≧7)), respectively, and then transferred from the top transport mechanism 8 to the external turntable S1 and returned to the wafer cassette via the EFEM.

[0106] The wafer on the proximity table P1 is unloaded to the working position W1 by the polishing arm H1, and then transferred to S1 from the transmission structure 5 or the transport structure 7. The wafer on P2 is unloaded to the working position W2, then translated to the working position W1, and then transferred to S1 by the transmission structure 5 or the transport structure 7. The wafer is then transferred from P1 and P2 to the wafer on the external turntable S1, and then returned to the wafer cassette via the EFEM.

[0107] Regarding the central polishing tables P3, P4 (and Pn, n < i), among them, the wafer located on the polishing table P3 is transferred to the working position W3 by the polishing arm H3, then transferred to the working position W2 by the transfer structure 5, then translated to the working position W1, and then returned to S1 by the transfer structure 5 or the transfer structure 7. The wafer on P4 is unloaded to the working position W4 by the polishing arm H4, and then transferred to S1 by the top unloading mechanism, or the wafer on P4 is unloaded to the working position W4 by the polishing arm H4, then translated to the working position W3, then transferred to the working position W2 by the transfer structure 5, then translated to the working position W1, and then returned to S1 by the transfer structure 5 or the transfer structure 7. The wafers unloaded from P3, P4 (and Pn, n < i) to S1 are sequentially returned to the wafer cassette via the EFEM.

[0108] Embodiment 6 The double disk process will be described by way of example.

[0109] There are multiple combination forms for the double disks. Mainly, it can be divided into two types: the three - set double disk process of the parallel disk set, and the double disk process with an alternating combination where the wafer transfer in the conventional structure is realized only by the top transfer mechanism 8. In the case where one of the polishing modules, for example, the polishing table P5 fails, or the polishing units are alternately combined, for example, in the P5 - P4 double disk process, the wafer that has completed the first polishing on the polishing table P5 is unloaded to the working position W5 and then clamped to the ascending position by the top transfer mechanism 8, then transported to the vertical ascending position of the load position W4 corresponding to the polishing table P4 disk, then further lowered to the W4 position, and further loaded to the polishing table P4 position by the polishing arm H4 and controlled to complete the second polishing.

[0110] After applying the transfer method of the present invention, the wafer unloaded from working position W5 can be quickly transferred to working position W4 by transfer mechanism 5 and then loaded by polishing arm H4 to complete the second polishing. The transfer method of the present invention significantly shortens the wafer transfer time between two polishing passes and reduces the risk of introducing defects into the wafer during the contact process of multi-step transfer. Alternating transfer also reduces the risk of wafer damage due to congested transfer in the event of a localized breakdown.

[0111] In this embodiment, the transport scheduling will be outlined using the transport processes, which are parallel double-disk processes with the highest efficiency (the least number of inter-disk transports), namely, the P1-P2 group, the P3-P4 group, and the P5-P6 group (Pi-Pi+1 (i≧7) group). As shown in FIG. (1) Remote table transport The remote table set P5-P6 (Pi-Pi+1 (i≧7)) transports the wafer transferred to the external turntable S1 via the EFEM by the top transport mechanism 8 to the working position W5, then loads it onto the polishing table P5 by the polishing arm H5 to complete the first stage of the planarization process (the wafer completes the first polishing), then unloads the wafer to the working position W5 by the polishing arm H5, then moves parallel to the working position W6, loads it onto the polishing table P6 by the polishing arm H6, then completes the second stage of the planarization process (the wafer completes the second polishing), then transfers the wafer to the working position W6 by the polishing arm H6, and then moves to S1 by the top transport device.

[0112] (2) Proximity table transport After the wafer is transferred from S1 to the working position W1 by the transfer structure 5 or the conveying structure 7, the proximity table set P1 - P2 is loaded onto the polishing table P1 by the polishing arm H1. After the first - stage planarization is completed, the polishing arm H1 transfers to the working position W1 and unloads. Then it translates to the working position W2. After the second - stage planarization process is completed, the polishing arm H2 transfers to the working position W2 and unloads. Then it translates to the working position W1 and is transferred to the external turntable S1 by the transfer structure 5 or the conveying structure 7. Thereby, in the conveying process, it is possible to reasonably schedule the conveying method of unloading from the working position W2 to the external turntable S1 according to the congestion degree of the top - conveying device and the conveying structure in this case.

[0113] (3) Central polishing unit conveyance Regarding the central table set P3 - P4 (and Pn - Pn + 1, n is odd, n < i)), for the wafer, there are multiple forms of entering the working position W3 (and Wn, n is odd, (Pn, n < i)) of the central conveying table. The first one is to directly carry it in from S1 to the working position W3 by the top - conveying mechanism 8. The second one is to translate from the working position W1 to the working position W2 by the transfer structure 5 or the conveying structure 7 and then transfer to the working position W3 by the transfer structure 5. The third one is to directly carry it in from the external turntable S1 to the working position W2 by the top - conveying mechanism 8 and then transfer to the working position W3 by the transfer structure 5. The fourth one is to directly carry it in from the external turntable S1 to the working position W5 by the top - conveying mechanism 8, then transfer to the working position W4 by the transfer structure 5, and then translate to the working position W3.

[0114] Obviously, the first and second transfer paths are more direct as they utilize only one of the two transfer devices compared to the latter two types. The wafer located at the working position W3 is loaded onto the polishing table P3 by the polishing arm H3 and transferred. After undergoing the first-stage planarization and being transferred back to the working position W3 and unloaded, it is translated to the working position W4, then loaded onto the polishing table P4 by the polishing arm H4. After the second-stage planarization is completed, it is transferred to the working position W4 to complete the unloading. After unloading, the wafer is similarly returned along the above loading path. Here, only the unloading methods corresponding to the former two types of transfers will be described. The first one is that the wafer is directly unloaded from the working position W4 to the external turntable S1 by the top transfer device. The second one is that after the wafer is translated from the working position W4 to the working position W3, it is transferred to the working position W2 by the transmission structure 5, then translated to the working position W1, and then unloaded to the external turntable S1 by the transmission structure 5 or the transfer structure 7, or unloaded by the combination of the top transfer mechanism 8 and the transmission structure 5.

[0115] Embodiment No. 7 [[ID=​​​​​​​​​​In the case of the remote table set, the wafer on the external turntable S1 is transported to the working position W6 by the top transport mechanism 8, then loaded onto the polishing table P6 by the polishing arm H6 to complete the first-stage planarization, then transferred to the working position W6 by the polishing arm H6 and unloaded, then translated to the working position W5, then loaded onto the polishing table P5 by the polishing arm H5 to complete the second-stage planarization, then transferred to the working position W4 by the transmission structure 5, then loaded onto the polishing table P4 by the polishing arm H4 and transferred, and then the third-stage planarization. After completing the planarization process, the wafer is transferred by the polishing arm H4 and unloaded to the working position W4, and after unloading is completed, it is directly transferred to the external turntable S1 by the top transport mechanism 8 and returned to the EFEM to be placed in a wafer cassette; alternatively, the wafer is translated from the working position W4 to the working position W3, then transferred to the working position W2 by the transmission structure 5, then translated to the working position W1, and then transferred to the external turntable S1 by the transmission structure 5 or the transport structure 7, or transferred by a combination of the top transport mechanism and the transmission structure 5.

[0118] (2) Proximity table transport In the case of a pair of adjacent tables, there are two ways to load the wafer into the work position W1. One way is to use the top transport mechanism 8 on the right end to directly transport the wafer from the external turntable S1 to the work position W1. Alternatively, the wafer can be transported to the work position W1 by the transmission structure 5 or the transport structure 7. The wafer positioned at W1 is loaded by the polishing arm H1 and transferred to the polishing table P1 to complete the first stage of planarization. Then, the polishing arm H1 is transferred to the work position W1 and unloaded. The wafer then moves parallel to W2, is loaded by the polishing arm H2 and transferred to the polishing table P2 to complete the second stage of planarization. Then, the polishing arm H2 is transferred to the work position W2 and unloaded. Finally, the wafer is transferred to the work position W3 by the transmission structure 5, is loaded by the polishing arm H3 and transferred to the polishing table P3 to complete the third stage of planarization, and then transferred to the work position W3 and unloaded. The wafer located at the working position W3 has two kinds of transport paths, one of which is the transport path that is directly returned to S1 by the top transport mechanism 8 on the right side, and the other way is to move to the working position W2 by the transmission structure 5, then move parallel to the working position W1, and then be transported to the external turntable S1 by the transmission structure 5 or the transport structure 7, and finally be returned to the EFEM and put into the wafer cassette, or the transport path that is transported by the combination of the top transport mechanism and the transmission structure 5.

[0119] If the polishing module 11 is larger than the polishing module 11 and the total number of disks exceeds six, the third stage flattening process should be located on the central disk as much as possible in order to simultaneously consider efficient scheduling of the top transport mechanism 8 and the transmission structure 5.

[0120] The above specific embodiments are intended to explain and illustrate the present invention, but are not intended to limit the present invention. Any modifications or changes made to the present invention within the spirit of the present invention and the scope of the claims are also included in the scope of the present invention.

Claims

1. 1. A wafer polishing system including a polishing unit having a wafer transport channel having at least two working positions, and a polishing module including a polishing table and a polishing arm capable of moving a wafer relative to a drive of the polishing table to perform a polishing process, a wafer loading / unloading table is movable between the working positions, and a transfer structure is provided between adjacent polishing units to transfer wafers between the working positions along a first track on the wafer transport channel; and / or the wafer loading / unloading table is movable between adjacent polishing units, and / or a transfer structure is provided between the polishing unit and the external turntable to transfer wafers between the working positions along a second track on the wafer transport channel; a top transport mechanism that transports wafers between all of the polishing units along a third track on the wafer transport channel, or transports the wafers between any of the polishing units and the external turntable along a fourth track on the wafer transport channel; the top transport mechanism is located above the transfer structure and / or the transport structure; A wafer polishing system comprising:

2. the transfer structure includes a clamp unit for clamping the wafer, and an inversion unit for driving the clamp unit and the wafer to invert forward or backward within the wafer transfer channel.

2. The wafer polishing system according to claim 1.

3. the transfer structure includes a clamp unit for clamping the wafer, a translation unit for driving the clamp unit and the wafer so that they translate within the wafer transport channel, and an elevation unit for driving the transfer structure so that the entire structure moves up or down to be positioned below or above the polishing table.

2. The wafer polishing system according to claim 1.

4. The transfer structure includes a base and an extendable arm connected to the base, the extendable arm extending downward from an upper region of the polishing table or extending upward from a lower region of the polishing table.

2. The wafer polishing system according to claim 1.

5. the transfer structure includes an auxiliary work position located between adjacent polishing units and an auxiliary transfer unit provided above or below the auxiliary work position, and the wafer loading / unloading tables of the adjacent polishing units can both be moved to the auxiliary work position, the auxiliary transfer unit is used to suck the wafer on the auxiliary work position or to place the wafer on the wafer loading / unloading table on the auxiliary work position, and the auxiliary transfer unit is located below or above the polishing table; 2. The wafer polishing system according to claim 1.

6. a movement path of at least a part of the wafer loading / unloading table that can move between adjacent polishing units overlaps with another movement path, and at least one of the work positions is included within the overlapping path; 2. The wafer polishing system according to claim 1.

7. There is a gap between adjacent polishing units.

2. The wafer polishing system according to claim 1.

8. The transmission structure is provided between adjacent working positions of the same polishing unit.

2. The wafer polishing system according to claim 1.

9. the transmission structure is the same as the conveying structure; 2. The wafer polishing system according to claim 1.

10. A wafer transport method for a wafer polishing system including a polishing unit having a wafer transport channel with at least two working positions, comprising: The wafer loading / unloading table is movable between the working positions, and the wafer transport method includes a transfer structure transporting the wafer from the working position of the polishing unit to the working position of another adjacent polishing unit along a first track on a wafer transport channel; a transfer structure for transferring the wafer from a working position of the polishing unit to an external turntable or from the external turntable to a working position of the polishing unit along a second track on the wafer transfer channel; the transfer structure and the wafer loading / unloading table are used to transport the wafer between working positions of the polishing unit along the first track until the wafer enters a target working position, and the polishing arm retrieves the wafer on the working position and moves it to the polishing table for a polishing process; or the top transport mechanism is used to transport the wafer between working positions of the polishing unit along the third track, and the wafer enters the target working position directly, and the polishing arm retrieves the wafer on the working position and moves it to the polishing table for a polishing process; or the transfer structure, the wafer loading / unloading table and the top transport mechanism are used to transport the wafer between working positions of the polishing unit along the first and third tracks, all of which are on the wafer transport channel, until the wafer enters a target working position, and the polishing arm retrieves the wafer on the working position and moves it to the polishing table for a polishing process.

10. A wafer transport method for a wafer polishing system comprising:

11. The method includes using a top transport mechanism to transport the wafer from the external turntable to the working position of the polishing unit along the third track on the wafer transport channel.

11. The wafer transport method for a wafer polishing system according to claim 10.

12. the number of the polishing units is plural, the polishing process is divided into plural stages, and the polishing unit located in the downstream stage is installed close to the center of the wafer transport channel; 11. The wafer transport method for a wafer polishing system according to claim 10.

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